丝氨酸功能化石墨烯量子点的制备及用于环境水中Cr(Ⅵ)荧光检测  

Synthesis of serine-functionalized graphene quantum dots and its application in fluorescence determination of Cr(Ⅵ)in environmental water

作　　者：江燕红 李在均 JIANG Yanhong;LI Zaijun(School of Chemical and Material Engineering,Jiangnan University,Wuxi 214122)

机构地区：[1]江南大学化学与材料工程学院,无锡214122

出　　处：《分析试验室》2020年第12期1386-1391,共6页Chinese Journal of Analysis Laboratory

基　　金：国家重点研发计划(2018YFC1603001);国家自然科学基金项目(21576115)资助。

摘　　要：采用柠檬酸和丝氨酸的混合物于180℃下热解3 h得到丝氨酸功能化石墨烯量子点(Ser-GQD),Ser-GQD的石墨烯片尺寸为(3±1 nm),平均厚度1.2 nm,含有丰富的羟基、氨基和羧基等亲水基团。相对于柠檬酸热解制备的GQD,Ser-GQD具有更强的荧光发射和光学稳定性,说明丝氨酸的引入改善了GQD的光学性质。基于Ser-GQD的荧光激发光谱和荧光发射光谱与重铬酸钾的紫外吸收光谱重叠所引起的内滤效应,建立了测定Cr(Ⅵ)的荧光分析方法。当Cr(Ⅵ)浓度在0~500μmol/L,Ser-GQD的荧光与Cr(Ⅵ)的浓度呈良好线性关系,相关系数(R2)为0.9913,检出限达到0.0033μmol/L。方法已用于环境水中痕量Cr(Ⅵ)的测定。The serine-functionalized graphene quantum dots(Ser-GQD)were prepared by pyrolysis of mixture of citric acid and serine at 180℃for 3 hour.The graphene sheets of Ser-GQD had the sheet size of(3±1)nm with the thickness of 1.2 nm and the rich of hydrophilic groups such as hydroxyl,amino and carboxyl groups.The Ser-GQD offered a stronger fluorescence emission and optical stability compared with the GQD prepared by citric acid,verifying that the introduction of serine improves the optical properties of GQD.Based on the internal filter effect caused by overlapping of the fluorescence excitation and emission spectra of Ser-GQD and the ultraviolet absorption spectra of potassium dichromate,a fluorescent method was developed for determination of Cr(Ⅵ).The fluorescence signal had good linear relationship with the increase of Cr(Ⅵ)concentration in the range of 0-500μmol/L,with the determination coefficient(R2)of 0.9913 and the detection limit of 0.0033μmol/L.The analytical method has been successfully applied to the determination of trace Cr(Ⅵ)in environmental water.

关 键 词：丝氨酸功能化石墨烯量子点 荧光猝灭 六价铬离子 内滤效应 检测 

分 类 号：O657.31[理学—分析化学] X832[理学—化学]